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Detection Limits

Extremes and Environmental Risk

  1. David Walshaw

Published Online: 15 JAN 2013

DOI: 10.1002/9780470057339.vad015.pub2

Encyclopedia of Environmetrics

Encyclopedia of Environmetrics

How to Cite

Walshaw, D. 2013. Detection Limits . Encyclopedia of Environmetrics. 2.

Author Information

  1. Newcastle University, UK

Publication History

  1. Published Online: 15 JAN 2013

Abstract

In analytical chemistry, the detection limit is the lowest level of an analyte that can reliably be detected by a well-defined operating procedure. It is often confused with the decision limit, which is a threshold of measurement used to determine whether or not the analyte is present in a particular study. We discuss the history and confusion relating to the definition in a univariate context. We consider the detection limit as a function of the sources of variation within an operating procedure. Estimation of the detection limit assuming constant variance in one-level designs and calibration designs is described, as well as a brief treatment of the assumption of non-constant variance. We outline modifications for multiple future detection decisions. Finally we consider approaches to multivariate detection, when decisions are based on more than one quantitative signal.

Keywords:

  • minimum detectable value;
  • decision limit;
  • analytical chemistry;
  • quantitative univariate measurements;
  • multivariate detection